docs: def _get_spec(self) -> dict:
          """Fetches the OpenAPI spec from the server.
  
          If the spec has already been fetched, the cached version is returned instead.
  
          ArgS:
              None
  
          Returns:
              OpenAPI spec data
          """
          if self.spec:
              return self.spec
          self.spec = requests.get(self.SPEC_URL.format(self.version)).json()
          return self.spec